| Because coal will be the main form of energy supply in a long period of time,therefore,the efficient and clean use of coal has become a hot spot.Coal gasification to generate electric energy is one of the main forms of the clean utilization of coal,attracted much attention for its high efficiency and economical efficiency,but in the process,will produce a large number of sulfur gases,which will not only corrosion of pipelines and apparatus,but also do great harm to human health and the living environment,so it is crucial for the removal of sulfide.High temperature coal gas desulfurization technology as the most promising desulfurization technology at present,its operation cost is low,can also be used by recycling,so research on the regeneration process of high temperature coal gas desulfurization sorbent have important theoretical significance and application value.In this paper,the effects of regeneration temperature and gas concentration on the regeneration process of iron oxide and cerium oxide desulfurization sorbents were investigated by using a SETSYS Evolution?TG-DSC?.Then according to the thermogravimetric curves of the regeneration process,the regeneration kinetics parameters of iron oxide and cerium oxide desulfurization sorbent were calculated.Finally,the regeneration mechanism of iron oxide and cerium oxide desulfurization sorbents in O2,SO2 and O2-SO2 atmosphere was discussed by means of fixed bed experiment and XRD.The main experimental results are as follows:?When the iron oxide desulfurization sorbent is regenerated in O2,SO2 and O2-SO2 atmosphere,with the temperature or gas concentration increased,the regeneration rate is faster,the regeneration time is shorter,indication that the temperature or gas concentration is conducive to the regeneration of iron oxide desulfurization sorbent.?According to the experiment of TG curve were obtained iron oxide and cerium oxide desulfurization sorbents in O2,SO2 and O2-SO2 atmosphere in the process of regeneration mechanism,the mechanism of the three stages of the regeneration of the iron oxide desulfurization sorbent in the O2 atmosphere is:R2,the kinetic equation are d?/dt = 1.56×1013e-236.206/RT?1-??1/2,da/dt=6.42×1013e-138.591/RT?1-??1/2,da/dt=3.22×102e-127.531/RT(1-?1/2;the iron oxide desulfurization sorbent in the SO2atmosphere regeneration is divided into five stages:the first stage conforms to anti-Jander mechanism,the kinetic equation is???the second and fifth stages conform to R2 mechanism,the kinetic equationrespectively are???,the thirdstage conforms to E1 mechanism,the kinetic equation is???the fourth stage of regeneration conforms to A12.04 mechanism,the kinetic equation is the iron oxide desulfurization sorbent in the O2-SO2 atmosphere regeneration is divided into three stages:the first stage conforms to R1 mechanism,the kinetic equation is the second stage conforms to A1.05 mechanism,the kinetic equation is the third stage conforms to El mechanism,thekinetic equation is The cerium oxide desulfurization sorbent in the O2 atmosphere regeneration is divided into three stages:the first stage of regeneration conforms to A0.65 mechanism,the kinetic equation is the second stage conforms to A3.85 mechanism,the kinetic equation is the third stage of regeneration conforms to D4 mechanism,the kinetic equation is the cerium oxide desulfurization sorbent in the SO2 atmosphere regeneration is divided into four stages:the first stage conforms to D2 mechanism,the kinetic equation is the second and fourth stages conform to R2 mechanism,the kinetic equation respectively are the third stage conforms to E1 mechanism,the kinetic equation is;the cerium oxide desulfurization sorbent in the O2-SO2 atmosphere regeneration is divided into four stages:the first stage conforms to D2 mechanism,the kinetic equation is the second stage conforms to F2 mechanism,the kinetic equation is,the third stage conforms to E1 mechanism,the kinetic equation is the fourth stage of regeneration conforms toA5.71 mechanism,the kinetic equation is?Based on the regeneration condition of iron oxide and cerium oxide desulfurization sorbents in three kinds of atmosphere,we can conclude that the regeneration of iron oxide desulfurization sorbent is the best in O2-SO2 atmosphere,the synergistic ratio is O2:SO2=1:12,the regeneration of iron oxide desulfurization sorbent in O2-SO2 atmosphere,not only the minimum temperature required for regeneration complete,but also the most simple regeneration process,at the same time prevent sorbent sintering in single O2 atmosphere but also improve the problem of slow rate of regeneration in single SO2 atmosphere.While the best regeneration atmosphere of cerium oxide desulfurization sorbent is SO2 atmosphere,the sulfate produced in this atmosphere is the least,which is beneficial to the recycling of the sorbents. |
PDF Full Text Request